How would I figure out what the average inventory amount would be when calculating the inventory turnover ratio?

I haveInventory Turnover Ratio = COGS as 621,010 / ___?___

(a) Calculate the inventory turnover ratio for the month of January. If the industry average of the inventory turnover ratio for the month of January is 17 times, is the company managing its inventory more or less efficiently than other companies in the same industry